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Alpine and Meadow Ecosystems
4. ALPINE AND MEADOW ECOSYSTEMS
ALPINE AND SUBALPINE
ECOSYSTEMS, SPECIES, AND
EXPECTED IMPACTS
The picturesque scenes of snow-capped volcanoes
in the southern Washington Cascades are more than
just a tourist attraction; they are also the home to
a number of species, such as the elusive wolverine
(Gulo gulo), Cascade red fox (Vulpes vulpes), and
marten. From emerald, grass-covered hills, to the
rocky balds where you can find roaming mountain
goats (Oreamnos americanus) and American pika
(Ochotona princeps), to the pointed peaks with
year-round glaciers and dense winter and spring
snowpacks, the subalpine and alpine regions of the
Cascades play a very important role in the makeup
of the larger ecosystem and contribute to the
biodiversity that is essential to the survival of many
species in this region.
Features of the Alpine
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High elevations and cold, harsh weather
Low-lying grasses, shrubs and other uniquely-suited plants
Rocky soil
Presence of a distinct timberline
In the face of even mild to moderate warming,
we can expect to see a recession of glaciers and
the disappearance of snowpacks. Since subalpine
and alpine ecosystems depend on cold winters
and mild summers, they are considered one of the
most threatened ecosystems in our study area. Data
suggests that in regions of high altitude, the climate
is changing more rapidly than elsewhere. We could
easily see the disappearance of several notable
High elevation ecosystems are considered one
of the most threatened types of ecosystems in
the region
Photo by Adam Zucker
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glaciers in this region within the next century.
heat and avoid the harsh winds.
The alpine areas in the Southern Cascades
have a typical elevation from about 7,000’ to
14,410’ at the peak of Mt. Rainier. Substantial
snowpacks and year-round glaciers are an
integral part of the alpine biome. In our study
area of the Southern Cascades, glaciers cover
a total of approximately 80 mi2. The glaciers
and snowpacks, and their associated snowmelt, are integral parts of the
hydrological cycle. A healthy
buildup of snow and ice over
the winter ensures snowmelt
into and through the summer
months. An irregular amount
of snowfall and ice build-up
during the winter can lead
to snowmelt in the spring
and summer that is harder to
anticipate and that can lead to
drought or flooding. Further,
several species, like the
wolverine or cascade red fox,
are dependent on the snow and
ice for shelter, hunting, and
food storage.
As climate continues to warm, we can expect to
see the timberline encroach on upland habitat.
According to Gehrig-Fasel et al. (2007), current
warming at higher altitudes might be responsible
for the dramatic increase in the density and area of
tree growth rates in the timberline area (188). With
climate change, we can also expect to see an earlier
onset of spring and a decrease in snowpacks.
Extreme elevation, along with
high latitudes, creates cold
and harsh weather patterns.
A high volume of winter
snow, harsh winds, and cold
night temperatures create the
signature climate of the alpine,
which is home to a unique
array of plants and animals.
The cold climate, rocky soil,
and heavy wind make growth
difficult for large trees that
thrive at lower altitudes. A
distinct timberline marks the
transition from the conifer
forest to the alpine uplands
dominated by low-lying plants
that hug the ground to absorb the
Glaciers and alpine regions in the southern Washington Cascades
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Decreased snowpacks and the expected expansion of forests into
higher altitudes threaten species that rely on the cold, rocky, and
open terrain of the alpine region for survival. However, climate
is not the only limiting factor of tree growth into alpine areas,
the rocky terrain of the alpine provides little suitable soil for
significant roots to take hold.
According to Beniston (2003):
Because temperature decreases with altitude by 5-10°C/km, a
first-order approximation regarding the response of vegetation
to climate change is that species will migrate upwards to find
climatic conditions in tomorrow’s climate which are similar
to today’s (e.g., McArthur, 1972; Peters and Darling, 1985).
According to this paradigm, the expected impacts of climate
change in mountainous nature reserves would include the loss
of the coolest climatic zones at the peaks of the mountains
and the linear shift of all remaining vegetation belts upslope.
Because mountain tops are smaller than bases, the present
belts at high elevations would occupy smaller and smaller
areas, and the corresponding species would have reductions
in population and may thus become more vulnerable to
genetic and environmental pressure (Peters and Darling, 1985;
Hansen-Bristow et al., 1988; Bortenschlager, 1993).
Mountain Goat
Oreamnos americanus
In the shadow of Mount St. Helen’s north facing crater, we are
seeing the development of North America’s newest glacier. While
the forming of this glacier is an important development, this is the
only glacier in the Washington Cascades that is not shrinking as a
result of warming temperatures.
Wolverine
Gulo gulo
“Impacts from climate change
are already occuring in alpine
regions.”
Flowering plants in subalpine meadows have started to flower
earlier in the season and this shift is expected to continue.
Substantial shifts in flowering have the potential to disrupt
relationships among plants, animals, fungus, bacteria, and
particular species that act as pollinators, seed dispersers,
herbivores, seed predators, and pathogens (189). Earlier snow
melt and warmer temperatures as a result of climate change will
cause subalpine meadow plant species to flower earlier and for
longer periods. These expected snow and temperature patterns
will likely lead to a loss of certain subalpine meadows from an
American Pika
Ochotona princeps
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increase tree establishment in subalpine areas and
severe impacts to plant species of the subalpine
region (69, 190).
Alpine and subalpine habitats in the southern
Washington Cascades are naturally isolated and
small in size because their occurrence is restricted to
higher elevations. Large distances between habitats
makes connectivity for alpine- and subalpinedependent species difficult. If not given direct
attention and managed in an adaptive and responsive
manner, we could witness the loss of these specialist
species and a significant decrease in rare upland
plants such as Alaska cedar and limber pine.
Because alpine and subalpine areas of the region
are particularly sensitive and responsive to shifts
in climate, they are valuable scientific indicators of
change.
Mountain goats are found in the high elevation
lands around Mount Adams, Mount St. Helens,
Goat Rocks, and Mount Rainier. Their thick white
coat provides both camouflage in the snow and
insulation against the harsh winter elements. They
are most typically found in rocky terrain where their
natural ability to climb makes them difficult prey for
predators. Mountain goats are dependent on grasses,
low-growing shrubs, and mosses for sustenance.
Because of their size and the typically low levels of
nutrients in alpine and subalpine plants, mountain
goats can also be found making pilgrimages to
known mineral licks that give them the essential
nutrients they need.
Mountain goat populations in the Washington
Cascades have declined over the past 50 years and,
while not currently an endangered species, they are
expected to face stressors as alpine and subalpine
habitats transform. They will likely suffer from a
decrease in late season forage in rocky outcrops
(31). An encroaching tree line and warming
climate is expected to restrict their habitat and, as a
result, reduce their grazing land and the amount of
accessible food.
The reduction of snowpack is expected to
significantly impact the wolverine, which relies
on snow for denning and caching prey (191–193).
Wolverines have specific adaptations to snow,
such as enlarged feet and insulating fur. Although
previously thought to be a habitat generalist,
recent studies have found the reproductive dens of
wolverines to be limited to areas that retain snow
during the spring. The reasons for their general
avoidance of areas without late spring snow is
unknown, but it is likely to avoid summer heat,
remain around suitable prey populations, and stay in
areas where their food caches are kept frozen (191).
In 2010, the wolverine was listed as a “Candidate”
species under the Endangered Species Act. In 2014,
a proposed rule to list the wolverine as “Threatened”
was withdrawn by the U.S. Fish and Wildlife
Service, but that decision was widely questioned
and eventually disputed by a federal court. The
proposed rule is currently being considered again.
With shrinking habitat areas, oftentimes to narrow
elevation bands, protecting wolverine habitat will
require identifying habitat, mapping corridors,
and enacting policies to limit influences known
to negatively impact wolverine survival and
reproduction, such as snowmobile activity near den
sites and tree encroachment (194).
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The American pika is a charismatic
relative of the rabbit, adapted for rocky
terrain and cold weather. American
pikas are typically found living inbetween the cracks and crevices of
boulder fields that are at or above
the subalpine tree line. As a diurnal
species, they are active during the day
foraging and collecting haystacks of
food that can last them over the winter
months. Like other native species
of the upland regions that thrive in
colder habitats, climate change poses
a potential threat to pikas. However,
there is evidence that pikas can move
into and survive in lower elevations
away from snow-dominated peaks
(195). It is unclear whether pikas will
be adaptable or dramatically impacted
by climate shifts.
Mount Rainier
25 glaciers cover
57 mi2
Goat Rocks
4 glaciers and
snowpack
cover 3 mi2
Mount St. Helens
1 glacier covers
about 1 mi2
Mount Adams
12 glaciers cover
15 mi2
Well-shaded dens and thick snow
packs create cooler microclimates
that shelter this sensitive species
Data show that glaciers on Mount Rainier, Goat Rocks, and Mount Adams have
from warming temperatures. Because
all been shrinking over the last several decades and suggest that we could see
their resting body temperature is
the disappearance of several of these glaciers over the next century.
only a few degrees below lethal body
temperature, pikas can be sensitive
to temperature extremes (196).
these findings in that region might overlap with our
Pikas seem to be most vulnerable,
own pika populations in the southern Washington
though, to extreme weather events (196). Climate
Cascades has yet to be fully understood, though,
models suggest increasing summer drought and
and will depend on connectivity and suitable habitat
freezing rain over the winter months. Freezing
availability at lower elevations.
rain can incase plants necessary to the pika diet
in ice and render them inedible; while drought
The Cascade red fox, an already rare species,
and earlier snowmelt can reduce the snow packs
could see new stressors from competition as
that pikas sometimes depend on for both shelter,
other carnivores migrate. Habitat alterations in
temperature regulation and food storage. Already
the uplands may also hinder population viability
living at elevations between 8,000-14,000 feet,
of hoary marmot, marten, and white-tailed
many pika populations do not have the luxury of
ptarmigan (31).
being able to extend their range upward in elevation
because they already exist near the upper limits
(197). In areas like the Great Basin of the Rocky
Mountains researchers have found pika populations
disappearing from 8 of 25 mountain locations in
connection to the warming temperatures (198). How
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and Meadow Ecosystems
Mount
Rainier
Just north of Gifford Pinchot National Forest, in the
northern portion of our study area, stands the iconic
white slopes of Mount Rainier. A familiar site behind
While the work done in this national park is an exemplar
for forest managers throughout the country, there are
still climate related threats that will require innovative
strategies in ecosystem management.
the Seattle and Tacoma skyline, this volcano is one of
The approximately 92 square kilometers (57 mi2) of glacier
the most photographed and recognizable geological
formations, make Mount Rainier the most glaciated peak in
formations in North America. Recognized early on for
the contiguous United States. Year-round snowmelt at the
its magnificent landscape, legislation to establish Mount
peak creates six major rivers that make the lush landscapes
Rainier as a national park was supported by people from
at the basin possible. Unfortunately, as discussed in the
all walks of life. In 1899, Mount Rainier National Park
Alpine and Meadow Habitats section of this guidebook,
became the 5th national park and established a precedent
climate change represents an especially large threat to
for conservation and preservation in this region.
the glaciers of these alpine regions. According to Ford
Home to nearly 300 different vertebrate species, and
countless more invertebrates, this national park contains
an undeniably diverse ecosystem. The continued
(2001), “these glaciers shrank 22% by area and 25% by
volume between 1913 and 1994 in conjunction with rising
temperatures.”
protection of the land and the biodiversity within it
With a range of winter and summer activities, Mount
makes Mount Rainier a haven for native wildlife. In order
Rainier is a popular attraction for winter recreation and
to protect this natural habitat, 97% of the national park
summer hiking and camping. In recent years, Mount
has been designated as protected wildlife areas. With
Rainier has attracted nearly 2 million visitors every year.
a strong history of nature conservation, Mount Rainer,
While a testament to the splendor of this national park, this
along with the Gifford Pinchot National forest, has been
high volume of visitors is a constant challenge for forest
selected as one of the two main sites to reintroduce the
managers and stewards. As temperatures rise due to climate
fisher into the Cascades. At any given time, dozens of
change, continued efforts to manage the impacts of tourism
research, monitoring, and conservation projects are being
are increasingly important. The preservation of this park,
carried out in this park to better improve understanding
and others like it, is dependent on continued research on
of the environment and contribute to the ever growing
climate change and the associated consequences.
literature on best practices for forest
managers and policy makers.
.
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Alpine and Meadow Ecosystems
MEADOWS
Meadows of the southern Washington Cascades
span the region and range from the low-elevation
wet meadows south of the Dark Divide to the dry,
alpine meadows of Mount Adams. Meadowlands
house unique configurations of plants and animals
that are not found in the surrounding forest
landscapes.
“Meadows filter sediment from runoff;
provide breeding grounds for invertebrates,
which serve as a food source for many
birds, amphibians, and reptiles; and
provide habitat structure for birds and
small mammals, which are a prey base for
raptors and other carnivores.” –Ford 2001
Meadow habitats are important pieces of the
broader ecosystem puzzle and are vital components
of a healthy Pacific Northwest ecosystem.
Threatened and rare species, such as pale blueeyed grass (Sisyrinchium sarmentosum) and the
mardon skipper butterfly (Polites mardon)
rely on meadows. As the primary breeding
ground for invertebrates, the meadows in the
southern Washington Cascades play a critical
role in supporting continued biodiversity through
pollinators and by providing sources of food for
birds and small mammalian species. Meadows
of the region support a wide array of butterflies,
including skippers, checkerspots, fritillaries,
sulphers, blues, and swallowtails (31). Chipping
sparrow, hermit thrush, yellow-rumped warbler,
and Townsend’s warbler nest at the edges
between meadows and conifer forests. A variety
of mammals, such as bear, deer, elk, and goldenmantled ground squirrel also regularly use meadow
habitat (31). Transitory species rely on connected
meadow habitat to ensure genetic diversity and
adequate availability of habitat in the event
of a major disturbance, such as forest fires or
streambank flooding.
“Shrubs from dry meadows may move into
wet meadows and displace flowering plants,
which can affect elk, butterflies, and a
variety of birds.”
The drier summers we can expect to see will
have impacts on many of the plant species found
in meadows, some of which are critical to local
pollinators (81, 199). Impacts, though, will depend
on topography and meadow type. The loss of
critical plant species can disrupt the mating cycle
of invertebrates or drive them out of the region
entirely. Some of the best pollinating species, such
as the mardon skipper butterfly, are limited by their
non-migratory behavior. One of the concerns with
non-migratory, pollinating invertebrates is that their
habitats are becoming smaller and increasingly
disconnected.
Mardon skipper butterflies, due to their habitat requirements and nonmigratory behavior, are at risk from an increase in habitat disturbances
from climate change. Photo by Tom Kogut
Warmer temperatures will likely bring threats from
invasive species such as Scotch broom and vetch
as well as a general loss of heterogeneity (200,
201). Already, as temperatures have increased,
perennial flowering plants in some places have
been replaced by low lying shrubs and sedges that
are better equipped for warmer and drier weather
(199). In the wetter meadows, this shift of plant life
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will be additionally harmful to the food stock of
animal species that are not able to find the required
nutrients from the sedges and shrubs. The increase
in shrub-like plants and decline of floral plants has
serious implications for pollinators and continued
vegetative diversity (202).
“Wet meadows are saturated with water for
much of the growing season. Moist meadows
may be flooded soon after snowmelt, but
may not stay saturated as the water table
lowers. Dry meadows may experience
intermittent flooding but are well-drained
and have a deeper water table than wet or
moist meadows.” –Southwest Washington
Adaptation Partnership 2016”
While not always the case, dry meadows tend
to exist in the basin and wet tend to exist in the
alpine and subalpine habitats. Climate shifts will
likely favor dry meadows, which are adapted to
warmer weather and seasonal drought, over wet
meadows, which are dependent on consistent
hydrology patterns in wet growing seasons (31).
Dry meadows are expected to expand while wet
meadows will likely shrink or transition to dry
meadows. Summer droughts can threaten native
plants in wet meadows that are not as effective
at water storage as larger trees or shrubs. Dry
meadows may, however, also respond negatively
if flooding and drought shifts increase to degrees
that cause significant die-off of flowering plants.
Increased flooding events in dry or wet meadows
may also further promote tree encroachment.
Lost Meadow in the Gifford Pinchot National Forest. Photo by Shiloh Halsey
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Alpine and Meadow Ecosystems
STRATEGIES AND RECOMMENDATIONS FOR ALPINE AND
MEADOW HABITATS
STRATEGIES AND RECOMMENDATIONS
FOR ALPINE AND MEADOW HABITATS
ALPINE and SUBALPINE HABITATS
• Because of the uncertainty in climate response,
continued research on climate change and
conservation practices should be expanded.
The data tracked and reported by Snotel sites
throughout the region
are important for
understanding the
region’s precipitation
patterns. Efforts like
these, from the U.S.
Forest Service and
Natural Resources
Conservation Service, are
important for researchers
and forest managers alike
in order to determine
optimal restoration and
conservation strategies
moving forward.
• Where threatened from
logging, development, or
heavy recreation, protect
and actively restore
subalpine areas to create
and maintain habitat for
high elevation plants and
animals. Focus areas in
the southern Washington
Cascades include the
southern and western slopes of Mount Adams and
Mount Rainier.
• Consider forest thinning strategies that limit the
size and severity of uncharacteristically severe and
large fires moving into subalpine areas less able to
tolerate strong wildfires, such as in some subalpine
areas on the west side of Mount Adams.
• Increase collaboration and project partnerships
involving Mount Rainier National Park and
Okanogan-Wenatchee National Forest to support
connected alpine and subalpine habitat for upland
species such as wolverine, marten, and fox.
• Monitor tree mortality
and current areas of
alpine refugia (from a
vegetative perspective)
to identify where projects
should be focused, what
trees should be considered
for conservation and
restoration, and to
determine connectivity
pressures.
• Monitor vegetation
expanding into areas
previously covered in
snow.
• Monitor regrowth after
disturbance.
• To mitigate a loss
of biodiversity from
increased disturbance,
coordinate citizenagency-NGO efforts to collect cones and seedling
for future population viability as new plant zone
uncertainties become clearer and new restoration
projects are outlined for particular areas and
species.
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• Advocate for less snowmobile activity near
wolverine habitat to reduce negative habitat and
population impacts (194).
MEADOWS
• In the southwestern foothills of Mount Adams,
the establishment of Research Natural Areas
(RNAs) or Botanical Special Areas (BSAs) would
be a fitting approach to support ongoing meadow
restoration efforts while also ensuring more longterm focus on impacts and improvements. Possible
locations for new areas include: Lost Meadow,
McClellan Meadow, and Skookum Meadow.
Climate change adaptation strategies can represent
an opportunity to re-establish this dynamic by
offering a broader contextual blueprint that
highlights the need to let fires burn, support the
natural creation of meadow habitat in areas close
to current meadowland, consider the role of
subpopulations and genetic diversity in planning,
work from natural biotic or topographic features
that can shape long-term resilience and create
functional diversity, and to eventually allow
encroachment as part of the larger and revolving
system.
• Pond and plug restoration, which is basically
the building of partial dams along certain parts of
a stream channel, can reroute flow and increase
saturation in meadowlands (202). This technique
can improve the resilience of wet meadows and
help support a more diverse plant community. This
mirrors the work of beavers.
• Take advantage of opportunities to support the
natural creation of new meadow habitat in postfire areas and pursue designations to protect them
as such. In areas where meadow patches would
improve resilience for whole populations (i.e.,
nearby other meadows and subpopulations of
meadow species), certain post-fire stands 10 to 50
acres in size can be replanted with native meadow
species and then left to mature and persist with
little follow-up management, aside from periodic
(and only initial) pruning of encroaching conifers.
• Restoration of existing meadow habitat is
also currently needed to prevent encroachment
from surrounding conifer trees. The natural
sway of conifer encroachment would ideally
occur while other meadow patches are naturally
developing, thereby creating a pulsing mosaic of
meadow patches that support meadow species
at the landscape scale by being less impacted by
catastrophic disturbance at a local scale. Due to
past forest management, fire suppression, and
the patchwork of management on the landscape,
this natural gain and loss has not been occurring
in a manner that would support meadow species.
Wildlife and Climate Resilience Guidebook